.mvideo {
    position: absolute;
    width: auto;
    height: auto;
    min-width: 100%;
    min-height: 100%;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
}

.mvideocon {
    position: fixed;
    height: 100%;
    overflow: hidden;
    max-width: 100%;
    right: 0px;
    left: 0px;
    bottom: 0px;
    background-color: black;
    z-index: -1;
}